Ok so here is how I read it

when using a solid cam or solid roller and Harland Sharp rockers we want to restrict or control the amount of oil going to the heads.
One way of doing this is to groove No4 cam journal for full time oiling then drill and tap the oil passage in the head and screw in a .070 holley main jet into it?

correct?

That is one way, I have bought and am using some of the World blocks, they oil the rocker full time by the rocker arm oiling passage fed directly from the right side lifter oil galley,not through the cam They have a .040 restrictor in them stock I have used .039 restrictors successfully on several stock blocks with full time oiling to the rockers like your suggesting on Harlnad Sharp rockers, same size(.039) on several other motors with Indy heads with external full time oiling with H.S. rockers also On a extruded aluminum or any non needle bearing rockers I may end up using a bigger restrictor(.080) to start with and then decde to change it up or down on the size dependent on the results IHTHs

.039? that's pretty small

wouldn't a hose with smaller inside diameter work too on indy heads

I am afraid to use a smaller jet[.100] edl vic heads but I use a Mig tip in the rocker stand.I do not want to confuse a oil drain issue with too much oil.Good luck with what you decide.

What heads?

I drill a set set screw - then you don't have to drill out the oil passage so big for a jet. I'm using a .062 hole for Harland Sharp rockers.

You should try the Holley fuel jets... they come in all sizes

Muscle Motors did a world block for me and I wish they had read Andy Finkbeiners book cause it says in there to bush lifter bores to control over oiling the top end. They relized this on the dyno when it filled vacuum pump puke tank, or maybe when it sucked the pan dry. Their bandaid was to use pushrods with restrictors. This will make lifters hemmorage oil every time lash is taken up and increase windage and cause low oil psi, 15-20 psi at 1200rpm at 150 degrees. I guess since this was their first World block build it was just a learning curve.

When using an oil restrictor should you always prime the shaft before startup to prevent a dry system problem? Or lube the PR,valve tips and run it?Thanks Mr.P I was too lazy to use a pin drill of .070 and used a .100.I will look at the Holley jets closer to use.I will check if the holley jet will fit in the rocker stand.[1/4" hole]
ps: The holley jet is .310 so it can be made to fit a 1/4".